Typical flexible shafts are susceptible to torque to the extent that rotation of one side of the shaft does not correlate to rotation of the opposite side of the shaft. For instance, in applications where a shaft is used to transmit torque along a tortuous path to a remote device, it is desirable to maintain a correlation between rotation on one side of the shaft to rotation at the remote device such that the amount of rotation at the remote device can be tracked with certainty. Typical shafts are susceptible to buckling, kinking or require an excessive amount of initial rotation at the outset before correlatable torque transmission occurs. Accordingly, there is a need for a flexible shaft that transmits torque with improved certainty, adequacy and/or efficiency.